Concrete form tie and spacer



Oct. 3, 1950 c. KRAVAGNA CONCRETE FORM TIE AND SPACER Filed Jan. 15, 1948 FIG IO.

FIG. 4.

INVENTOR CUT KRAVAGNA BY ATTORNEYS Patented Oct. 3, 1950 UNITED STATES PATENT OFFICE CONCRETE FORM TIE AND SPACER Cut Kravagna, Los Angeles, Calif. Application January 15, 1948, Serial No. 2,395

This invention has to do with concrete form tie and spacer devices.

For a long time it has been a well known shortcoming of prior art form ties and spacers that they are so constructed as not to be adaptable to conditions which frequently arise in concrete forms. Such forms usually are built up of boards superimposed with their side edges in abutting relationship, with relatively thin spacers having end portions interposed between the edges of contiguous boards in the opposite spaced forms. Frequently the contiguous edges of the boards of one of the forms will be above or below the plane of the contiguousedges of the boards of the opposite form, and present tie and spacer devices are not well adapted for such conditions. Moreover, it sometimes happens that one end of the tie and spacer element must be anchored between horizontal form boards and anchored at the other end between vertically disposed form boards. Present devices are unsuited also to those conditions. Also, present devices are not well suited for spacing and tying the forms made of plywood or large sheets.

It is therefore an object of the present invention to provide a concrete form tie and spacer element which overcomes those shortcomings of prior devices in that, in my device, the form board engaging end portions are interconnected by a relatively narrow, thin, pliable web which is so easily deformable as to permit of adjustment to different form board positions but which at the same time possesses sufficient strength to maintain the forms suitably spaced.

Another object is to provide a device of this character which is extremely economical of manufacture. This feature is conducive to economy in construction operations since tie and spacer elements must remain in the set concrete after the forms are removed.

A further object is to provide a tie and spacer element which is suited for use in concrete forms composed of large sheets of plywood or the like.

A still further object is to provide a tie and spacer element of the character referred to which has means for securing the element to a form composed of vertically disposed boards while the form is being set up.

Still further objects and corresponding advantages will become apparent from the following description of a presently preferred embodiment of the invention, for which purpose I shall refer to the accompanying drawings, wherein:

Fig. l is a top plan view;

Fig. 2 is a fragmentary side elevation, taken on 1 Claim. (01. 25-131) line 22 of Fig. 1, but showing an end of the device interposed between the abutting edges of two form boards;

Fig. 3 is an end elevation taken on line 3-3 of Fig. 2;

Fig. 4 is a fragmentary elevation showing an end of my device secured to a vertical form board;

Fig. 5 is a reduced elevation showing my device mounted between horizontal form boards, and which at its other end is mounted between vertical form boards, the boards being shown in section;

Fig. 6 is a reduced elevation showing my device having its opposite ends disposed between sets of form boards whose abutting edges are at difierent planes;

Fig. '7 is a fragmentary plan view showing a modification of my invention;

Fig. 8 is an end elevation showing the device of Fig. 7 mounted in a form set;

Fig. 9 is a cross-sectional view showing a further modification; and

Fig. 10 is a plan view showing another modification.

Referring now to the accompanying drawings, Figs. 1-6, I show my improved concrete form tie andspacer device as comprising form-engaging end members 5, 5 interconnected by an integral, relatively narrow pliable web l.

Except that the ends 5, ii are disposed oppositely to each other, they are of the same construction and a description of one will s flice for both. Each of the ends has a pair of openings l5 separated by a web portion l5 and has oppositely bent V-shaped side portions H, H) terminating in side flanges i9, 29.

As best shown in Fig. 2, each of the ends is adapted to be disposed between the abutting edges of contiguous form boards B, Bf. When thus positioned, the oppositely bent portions ll, iii are disposed to engage opposite faces of the form board so as to provide lateralsupport therefor. Preferably, however, the holes l5 are slightly longer than the thickness of most form boards so as to accommodate forms of different thicknesses. Since wet concrete mix between the forms urges the forms outwardly, the boards engage the outer side walls of the holes IS. The ends 5, E are of very thin construction so as to provide only minimum spacing apart of the contiguous boards between which they fit.

To hold the end members in laterally spaced relation, they are interconnected by a relatively narrow, thin, pliable or deformable web or tension member 1, which Web is preferably reinforced longitudinally by a rib 25. As shown in Fig. 3, this rib 25 may be provided during the rolling of the sheets from which these devices are cut, or may be provided by embossing, as shown at 25a in Fig. 9. This rib extends lengthwise of the entire device, except that it is cut away medially of the end members between the holes 15 to provide openings 26. These openings are to permit the device to be tacked to a vertically disposed form in order to hold the tie and spacer element in position while the form is being assembled. See Fig. 4, wherein a tack 21 is used to tack an end to the form.

By having the ends disposed oppositely to each otherthat is, by having the respective V-bends I1 and I8 at one end disposed oppositely to the direction of the bends I! and H3 at the other end-if either the upper or lower form board of a form should be out of alignment with the contiguous board, the pull exerted by the device will be diagonally longitudinally from the corresponding opposite form board until the misaligned board is brought into alignment.

Preferably the entire device is made of a material which is pliable as distinguished from being resiliently flexible, because one of the chief advantages of providing the relatively narrow, thin connecting web I is that the web may be easily deformed to suit different concrete form con ditions. For instance, in Fig. 5, one of my devices is shown applied to a form, one of whose sides is composed of horizontally disposed boards and the other of whose sides is composed of vertically disposed boards C. To so relatively dispose the ends of the tie and spacer elements it necting web I, as shown at 30.

In Fig. 6 I show how the connecting web may be bent so that the ends may fit between form boards whose abutting edges are at different levels. Here the form boards B and D have their bottom edges abutting the contiguous lower form boards at different levels. To accommodate such a situation, an angular bend 3| is made in the connecting web I.

type of form-engaging end for my tie and spacer element which is peculiarly adapted for use in forms composed of large sheets, such as plywood sheets. Here instead of the shape of end as shown at 5 and 6 in Figs. 1-6, I use ends 35 each shaped as follows:

Each end 35 has a medial leg 36 which is in effect a continuation of the connecting web 1a, and has at the opposite sides of the medial leg, and spaced therefrom, pair of legs 31, 38. At each side of the inner end of the medial leg I provide opposite V-bends 39, 46 which correspond to the bends l7, l8 hereinabove described and serve to connect the legs. Where plywood or other large sheets are used as forms, there are relatively few abutting edges of the form sheets so that it is necessary to use tie and spacer elements at points other than between the abutting is only necessary to make a 90 twist in the con- 51,45 In Figs. 7 and 8 I show the use of a different edges of the sheets. By the use of the device shown in Figs. 7 and 8, it is only necessary to provide an elongated hole 4| through the form sheet, of a width to pass the thin legs 36, 31, 38 longitudinally. After the legs are inserted through the hole they are bent at right angles as shown in Fig. 8 to provide outward lateral support, and nails N are inserted through holes provided in the end portions of legs 35, 36, 31. The V-bends 39, 49 provide inward lateral support. In this adaptation of the invention the connecting web 1a may be bent or deformed in the manner before described to suit varying form conditions.

After the concrete mix has been poured into a form whose opposite sides are tied and spaced by my devices, and after the concrete has set, the forms may be stripped from the concrete and the projecting ends of the tie and spacer elements are then cut off flush with the outer surfaces of the wall, the connecting webs remaining in the set concrete.

In Fig. 10 I show a variational form of my invention wherein, instead of making the web 1 flat and integral with the ends as before described, I substitute a pliable length of wire 50 which is secured at its ends to the respective end members 5a of the construction before described, as follows: Each of the end members 5a has an extension 52 providing a pair of ears 53, 54 which are bent oppositely over the wire, and the end of the wire is bent at right angles an inserted through a, hole 55 in the extension.

In a concrete form board tie and spacer device, a body having a thin, flat, pliant, relatively narrow elongated tension portion defining the longitudinal axis ofthe body, and having at each end a relatively wide portion presenting a plurality of transversely spaced, axially disposed, pliant, flat prongs insertable through a slit in a form, said prongs being held separated by intervening portions bent out of the plane of -the prongs and tension portion to provide abutments for the inner face of a form.

CUT KRAVAGNA.

REFERENCES-CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 

